Category Archives: Agriculture

Food shortages brought on by extreme weather events have resulted in almost a quarter of Sri Lanka’s 21 million people becoming malnourished, says a World Food Programme (WFP) document.

“The increased frequency of natural disasters such as drought and flash floods further compounds food and nutrition insecurity,” says the document, the latest WFP country brief for Sri Lanka, released in June.

As per WFP’s most recent Cost of Diet Analysis, almost 6.8 million (33 per cent) Sri Lankans cannot afford the minimum cost of a nutritious diet and a large portion of this vulnerable population lives in poverty and is frequently subjected to extreme weather events.

Loss of land and livelihood from flooding caused to erratic monsoon rains. Image from Flickr.

In May heavy rains, brought on by Cyclone Roanu, affected 340,000 persons in 22 of the island’s 25 districts. “These people have very limited coping mechanisms, and these kinds of disasters can drive them deeper into poverty,” says minister for disaster management Anura Priyadarshana Yapa.

After the landslides and rains the government decided to shift out those living in high-risk areas but, according to public officials, they were faced with the problems of locating safe land and making income from agriculture.

“Most of those living on these high-risk areas rely on agriculture and we need to see how to secure their livelihoods,” head of the disaster management centre, Kegalle district, tells SciDev.Net.

The UN estimates that every year around 700,000 Sri Lankans are impacted by extreme weather, some repeatedly. “A sizeable segment of the flood affected population are squatters living in vulnerable areas prone to frequent flooding,” the UN Office for the Coordination of Humanitarian Affairs said following estimates made soon after the May floods and landslides.

“We need to develop long-term solutions, not stop-gap answers,” says Yapa, agreeing that there were serious problems arising from erratic weather patterns in Sri Lanka in recent years.

Scientists have found a potentially large carbon sink in the most unlikely place on Earth – under the desert. The increase in carbon storage is linked with the rise of farming in arid landscapes.

This surprising conclusion comes from work done in the Tarim Basin of western China by Chinese and American scientists. The results are published in the journal Geophysical Research Letters.

“Basically, people thought the whole arid region is totally negligible to the global carbon budget,” says lead author Yan Li of the Chinese Academy of Sciences in Urumqi. “We are arguing that that’s not the case.”

Li and colleagues measured and dated the carbon content of water samples taken from a salty aquifer beneath the Tarim Basin. They show that the rate at which carbon sunk into the aquifer rose dramatically with the rise of farming and agriculture in the region. Rate of carbon storage increased by more than 12 times previous levels over the past 8000 years with particularly high levels beginning around 2000 years ago when the Silk Road opened.

How it works

The process began when humans started to grow crops on sandy soil. As the plants take in carbon dioxide from the air, some is released into the sand. Farming in desert conditions requires a lot of water to combat rising salinity caused by rapidly evaporating water. This organic carbon dissolves in the water and is transported down through the sand into deed salty aquifers.

Normally these aquifers are tapped by rivers and streams and so the carbon comes back out of storage. But in the Tarim Basin the aquifer is a closed system, meaning that water does not escape, effectively locking away the carbon.

Li expects this process to occur in deserts around the globe but the amount of carbon would vary depending on the pH of the soil and the level of farming activity.

The results from this study will have important implications for the study of the global carbon cycle as desert regions were previously thought to be unimportant for carbon storage.

Like this:

With the World’s population now past 7 billion and projected to increase to 9 billion by 2050, stress on the food production system is at an all time high. To make matters worse it appears that our crop yields may fall victim to the effects of climate change.

Crop yields to drop by 25 percent towards the second half of the century.

Global warming of only 2°C will be detrimental to the production of rice, wheat and maize in temperate and tropical regions, with reduced yields from the 2030s onwards claims a study, published in Nature Climate Change last year, led by the University of Leeds scientists.

“Climate change means a less predictable harvest, with different countries winning and losing in different years. The overall picture remains negative, and we are now starting to see how research can support adaptation by avoiding the worse impacts,” says lead author Professor Andy Challinor.

The study shows that we will see, on average, an increasingly negative impact of climate change on crop yields from the 2030s onwards. The impact will be greatest in the second half of the century, when decreases of over 25% will become increasingly common.

These statistics already account for minor adaptation techniques employed by farmers to mitigate the effects of climate change, such as small adjustments in crop variety and planting date.

The IPCC projected temperature increase for the next century.

The latest Inter-governmental Panel on Climate Change (IPCC) reports state that the expected temperature increase for the end of the century is somewhere between 1.5 and 4 degree Celsius. And thus, major agricultural transformations and innovations will be needed in order to safeguard crop yields for future generations.